In order to advance our understanding of the micellization behavior of gradient copolymers,a gradient chain structure was introduced into the core-corona model of micelles.Different from block copolymer,a distinct junction point is absent in separation of A- and B- domain and the composition continuously changes from one end to the other along the chain for gradient copolymers.As a result,the solubility of the selective solvent,namely the Flory-Huggins parameter χ also changes continuously as a function of position along the chain.Once such gradient copolymers self assemble into micelles,the interface is much more diffuse and uncertain.